Extruder Calibration Tutorial: Do This For Smooth 3D Prints

When you are working with a 3D printer, it's like caring for a baby. You need to look after it and keep it well maintained. An essential part of this is regularly checking the extruder calibration. We no longer use meters or centimetre, because the most common unit now is millimetres and microns. Things can't get more precise than this!

Extruder calibration is a crucial step in ensuring your 3D printer produces high-quality prints consistently. It involves adjusting the various parameters that control the flow of filament through the extruder, such as the stepper motor steps per unit, the extruder multiplier, and the extrusion width. By getting these settings right, you can achieve optimal print quality, reduce waste, and extend the life of your 3D printer.

In this comprehensive tutorial, we'll walk you through the step-by-step process of calibrating your extruder, from gathering the necessary tools to fine-tuning the settings. Whether you're a seasoned 3D printing enthusiast or just starting out, this guide will equip you with the knowledge and confidence to master extruder calibration and take your 3D printing to new heights.

The extruder is the heart of your 3D printer, responsible for melting and pushing the filament through the nozzle to create your desired object. Proper extruder calibration ensures that the right amount of filament is being extruded, resulting in accurate dimensions, consistent layer heights, and a smooth surface finish.

When your extruder is not calibrated correctly, you may encounter a variety of issues, such as:

• Underextrusion: The extruder is not pushing out enough filament, leading to gaps, thin walls, and poor layer adhesion.
• Overextrusion: The extruder is pushing out too much filament, resulting in bulging, stringing, and potential clogging.
• Inconsistent layer heights: Varying layer heights can cause uneven surfaces and poor dimensional accuracy.
• Warping or deformation: Incorrect extrusion can cause the printed object to warp or deform, especially on the first few layers.

By calibrating your extruder, you can address these problems and ensure that your 3D printer is operating at its full potential.

Before you begin the extruder calibration process, make sure you have the following tools and materials on hand:

1. Calipers : A high-quality set of digital calipers is essential for measuring the dimensions of your printed parts accurately.
2. Filament : Ensure you have the same type of filament you'll be using for your regular prints, as different materials may require slightly different calibration settings.
3. Ruler or measuring tape : You'll need a ruler or measuring tape to measure the length of extruded filament during the calibration process.
4. Notepad and pen : Keep track of your measurements and settings as you go through the calibration steps.
5. Screwdrivers and Allen wrenches : You may need these tools to access and adjust the various components of your 3D printer.

With these tools in hand, you're ready to begin the extruder calibration process.

Callipers are devices that are used to precisely measure length, it’s like a ruler, but it is more advanced. I want to suggest that you should buy a digital calliper. These can be a bit expensive, but you will find that digital callipers are much easier to use. You will need to get calipers with at least 0.01mm precision or 0.0005 . You can typically buy these from a DIY store.

It’s always good to make a backup before any configuration changes. It doesn’t matter if you’re doing work on a computer, mobile phone or a 3D printer. Anything wrong can happen at any time, and this will result in you losing all the progress that you have worked on. So make sure that you do regular backups.

Okay, so to perform a backup of configurations for a 3D printer you will need Repetier Host this will be the software you will need to get before you can do anything else. You will need to connect your 3D printer using the USB cable provided, place this into a USB slot in your computer, and then press Control + P to open the configuration panel.

You can change the port, but I tend to leave it on auto, the  baud rates are usually ( 115200 – 250000 ) then press “ OK “. On the main screen, you will see connect (click this) then go into Config > Firmware EEPROM Configuration.

Now that you are on the EEPROM setting menu , click on export EEPROM data , I suggest you may want to take a print screen of the parameters in case you need to access a single value. After you have backed up your firmware, you can now start the extruder calibration.

You need to start by measuring your existing extruder calibration. This requires you to preheat the nozzle to liberate the extruder. Set the temperature to at least 170ºC. This is typically the failsafe temperature. After you have preheated the nozzle, you will then need to disassemble the extruder. This will be a lot easier if you have a Bowden system, but if you don’t, it’s okay. If your 3D printer has a direct drive extruder system, you will need to remove the hot end block with dissipator this will help the filament to more freely.

Another good idea is to check the extruder’s tensioner. I lose it won’t pull the plastic correctly!

Start to remove the Bowden tube from the snap-fit  locker. You can do this by pressing the plastic parts down, and then pull the PTFE Bowden tube up and out. Once you have finished removing the PFTE tube, you will then need to cut any excess filament away. Try to get it as close as possible to the end of the PTFE Bowden tube.

Once you have done the previews step, you will need to go back into Repetier host and “click on” extrude to 100mm.  Only press this once!  You will now have sent the extrusion commands, wait until the filament has stopped flowing out of the PFTE tube. Now, place the callipers with the left “ear” touching the PFTE tube and the right “ear” place it where the plastic ends. Using the digital callipers, it will display the value right away make sure you right this done. Make sure that the callipers have been ZEROED out before measuring. This is your initial extruder calibration.

You will need to go back in the EEPROM firmware setting, to do this a quicker way you can press ALT + E and then find where the E-Steps value is and write this down too, Do not close the firmware down as you will still need this up on the screen.

 You will need to calculate the steps. This can be a simple equation. For example

 The formula is: New _steps = old_steps (expected length / real length)

 One this case : New_steps = 157.16 ( 100 / 99,45 >>> New _steps = 158,0291

 Write the new value down on the firmware screen and press “ok.”  

After saving the final value on your 3D printer, you should measure the results again. This is because there may be a small error. Follow the previews instructions until you get exactly 100.00mm. After fine-tuning the extruder step/mm, you will then need to reassemble the PTFE Bowden tube or the hotend, for direct feed extruders.

Now you will have an extruder that is calibrated! You should not have any problems with over extrusion or under extrusion again. Remember to set the “extrusion multiplier” or “flow” to 100% on the slicer of your choice. Otherwise, it will override your extruder calibration!

To begin, you will need a calibration test model, there are hundreds on  Thingverse , but the one that most people will use is called  Benchy  . This model is designed to measure from specific points to ensure accurate printing, including dimensional accuracy, warping, deviations and tolerances.

After the print has finished, open the firmware configuration you will find the X , Y and Z steps/mm, put then into a calculator and measure the print with the callipers. The correct value should appear on the calculator, replace this into the firmware, remember to save everything and make a back up of the new value.

To be sure that everything is in working order, print this part again, the measurements should be within 0.05 of the expected value.

Remember that if your X and Y values are very different, your circles won’t be round.

This guide is not intended to fix bed levelling issues or bad quality filaments those are requirements for this calibration to work.

Are your prints still not looking great? Check out our guide for tuning your extrusion width!